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Hydrolase Inhibition (hydrolase + inhibition)
Selected AbstractsThe Potential of Soluble Epoxide Hydrolase Inhibition in the Treatment of Cardiac HypertrophyCONGESTIVE HEART FAILURE, Issue 4 2008Todd R. Harris PhD First page of article [source] PRECLINICAL STUDY: FULL ARTICLE: Effects of fatty acid amide hydrolase inhibition on neuronal responses to nicotine, cocaine and morphine in the nucleus accumbens shell and ventral tegmental area: involvement of PPAR-, nuclear receptorsADDICTION BIOLOGY, Issue 3 2010Antonio Luchicchi ABSTRACT The endocannabinoid system regulates neurotransmission in brain regions relevant to neurobiological and behavioral actions of addicting drugs. We recently demonstrated that inhibition by URB597 of fatty acid amide hydrolase (FAAH), the main enzyme that degrades the endogenous cannabinoid N-acylethanolamine (NAE) anandamide and the endogenous non-cannabinoid NAEs oleoylethanolamide and palmitoylethanolamide, blocks nicotine-induced excitation of ventral tegmental area (VTA) dopamine (DA) neurons and DA release in the shell of the nucleus accumbens (ShNAc), as well as nicotine-induced drug self-administration, conditioned place preference and relapse in rats. Here, we studied whether effects of FAAH inhibition on nicotine-induced changes in activity of VTA DA neurons were specific for nicotine or extended to two drugs of abuse acting through different mechanisms, cocaine and morphine. We also evaluated whether FAAH inhibition affects nicotine-, cocaine- or morphine-induced actions in the ShNAc. Experiments involved single-unit electrophysiological recordings from DA neurons in the VTA and medium spiny neurons in the ShNAc in anesthetized rats. We found that URB597 blocked effects of nicotine and cocaine in the ShNAc through activation of both surface cannabinoid CB1-receptors and alpha-type peroxisome proliferator-activated nuclear receptor. URB597 did not alter the effects of either cocaine or morphine on VTA DA neurons. These results show that the blockade of nicotine-induced excitation of VTA DA neurons, which we previously described, is selective for nicotine and indicate novel mechanisms recruited to regulate the effects of addicting drugs within the ShNAc of the brain reward system. [source] Mitochondrial S -Adenosyl- l -Methionine Transport is Insensitive to Alcohol-Mediated Changes in Membrane DynamicsALCOHOLISM, Issue 7 2009Anna Fernández Background:, Alcohol-induced liver injury is associated with decreased S -adenosyl- l -methionine (SAM)/S -adenosyl- l -homocysteine (SAH) ratio and mitochondrial glutathione (mGSH) depletion, which has been shown to sensitize hepatocytes to tumor necrosis factor (TNF). Aims:, As the effect of alcohol on mitochondrial SAM (mSAM) has been poorly characterized, our aim was to examine the status and transport of mSAM in relation to that of mGSH during alcohol intake. Methods:, Sprague,Dawley rats were pair fed Lieber,DeCarli diets containing alcohol for 1 to 4 weeks and liver fractionated into cytosol and mitochondria to examine the mSAM transport and its sensitivity to membrane dynamics. Results:, We found that cytosol SAM was depleted from the first week of alcohol feeding, with mSAM levels paralleling these changes. Cytosol SAH, however, increased during the first 3 weeks of alcohol intake, whereas its mitochondrial levels remained unchanged. mGSH depletion occurred by 3 to 4 weeks of alcohol intake due to cholesterol-mediated impaired transport from the cytosol. In contrast to this outcome, the transport of SAM into hepatic mitochondria was unaffected by alcohol intake and resistant to cholesterol-mediated perturbations in membrane dynamics; furthermore cytosolic SAH accumulation in primary hepatocytes by SAH hydrolase inhibition reproduced the mSAM depletion by alcohol due to the competition of SAH with SAM for mitochondrial transport. However, alcohol feeding did not potentiate the sensitivity to inhibition by SAH accumulation. Conclusions:, Alcohol-induced mSAM depletion precedes that of mGSH and occurs independently of alcohol-mediated perturbations in membrane dynamics, disproving an inherent defect in the mSAM transport by alcohol. These findings suggest that the early mSAM depletion may contribute to the alterations of mitochondrial membrane dynamics and the subsequent mGSH down-regulation induced by alcohol feeding. [source] Oleamide is a selective endogenous agonist of rat and human CB1 cannabinoid receptorsBRITISH JOURNAL OF PHARMACOLOGY, Issue 2 2004James D Leggett The ability of the endogenous fatty acid amide, cis -oleamide (ODA), to bind to and activate cannabinoid CB1 and CB2 receptors was investigated. ODA competitively inhibited binding of the nonselective cannabinoid agonist [3H]CP55,940 and the selective CB1 antagonist [3H]SR141716A to rat whole-brain membranes with Ki values of 1.14 ,M (0.52,2.53 ,M, Hill slope=0.80, n=6) and 2.63 ,M (0.62,11.20 ,M, Hill slope=0.92, n=4), respectively. AEA inhibited [3H]CP55,940 binding in rat whole-brain membranes with a Ki of 428 nM (346,510 nM, Hill slope=,1.33, n=3). ODA competitively inhibited [3H]CP55,940 binding in human CB1 (hCB1) cell membranes with a Ki value of 8.13 ,M (4.97,13.32 ,M, n=2). In human CB2 transfected (hCB2) HEK-293T cell membranes, 100 ,M ODA produced only a partial (42.5±7%) inhibition of [3H]CP55,940 binding. ODA stimulated [35S]GTP,S binding in a concentration-dependent manner (EC50=1.64 ,M (0.29,9.32 ,M), R2=0.99, n=4,9), with maximal stimulation of 188±9% of basal at 100 ,M. AEA stimulated [35S]GTP,S binding with an EC50 of 10.43 ,M (4.45,24.42 ,M, R2=1.00, n=3, 195±4% of basal at 300 ,M). Trans -oleamide (trans- ODA) failed to significantly stimulate [35S]GTP,S binding at concentrations up to 100 ,M. ODA (10 ,M)-stimulated [35S]GTP,S binding was reversed by the selective CB1 antagonist SR141716A (IC50=2.11 nM (0.32,13.77 nM), R2=1.00, n=6). The anatomical distribution of ODA-stimulated [35S]GTP,S binding in rat brain sections was indistinguishable from that of HU210. Increases of similar magnitude were observed due to both agonists in the striatum, cortex, hippocampus and cerebellum. ODA (10 ,M) significantly inhibited forskolin-stimulated cyclic AMP (cAMP) accumulation in mouse neuroblastoma N1E 115 cells (P=0.02, n=11). ODA-mediated inhibition was completely reversed by 1 ,M SR141716A (P<0.001, n=11) and was also reversed by pretreatment with 300 ng ml,1 pertussis toxin (P<0.001, n=6). These data demonstrate that ODA is a full cannabinoid CB1 receptor agonist. Therefore, in addition to allosteric modulation of other receptors and possible entourage effects due to fatty acid amide hydrolase inhibition, the effects of ODA may be mediated directly via the CB1 receptor. British Journal of Pharmacology (2004) 141, 253,262. doi:10.1038/sj.bjp.0705607 [source] |